Continuous-switching device for advancing the wheel mechanism of an electric clock

ABSTRACT

CONTINUOUS-SWITCHING DEVICE ADVANCING THE WHEEL MECHANISM OF AND ELECTRIC CLOCK, WHICH DEVICE COMPRISES A MOVEMENT-CONTROLLING OSCILLATOR PREFERABLY DRIVEN BY ELECTROMAGNETIC MEANS, A TWO-ARMED SWITCHING ARMATURE DRIVEN BY THIS MOVEMENT-CONTROLLING OSCILLATOR, AND A RATCHET WHEEL DRIVEN BY TEH SAID SWITCHING ARMATURE, CHARACTERIZED IN THAT THE SWITCHING ARMATURE (1) IS UNEQUALLY ARMED AND THE RATIO BETWEEN THE ARM LENGTH IS ABOUT 2:3, FURTHERMORE IN THAT THE ARMATURE APERTURE ANGLE EQUALS, OR EXCEEDS 90%, AND THAT THE DISTANCE (A) BETWEEN THE SWITCHING ARMATURE PIN (12) AND THE RATCHET WHEEL PIN (20) EQUALS OR EXCEEDS A VALUE OF 0.8 TIMES THE DIAMETER (D) OF THE RATCHET WHEEL (18).

Oct. 12, 1971 G. SCHOLZ 3,611,707

CONTINUOUS-SWITCHING DEVICE FOR ADVANCING THE WHEEL MECHANISM OF AN ELECTRIC CLOCK 2 Sheets-Sheet 1 Filed Nov. 12, 1969 Oct. 12, 1971 G. SCHOLZ 3,511,707

CONTINUOUS-SWITCHING DEVICE FOR ADVANCING THE WHEEL MECHANISM OF AN ELECTRIC CLOCK Filed Nov. 12, 1969 2 Sheets-Sheet 2 III I ll United States Patent 3,611,707 CONTINUOUS-SWITCHING DEVICE FOR AD- VANCIN G THE WHEEL MECHANISM OF AN ELECTRIC CLOCK Gunther Scholz, Schramberg, Germany, assignor to Messrs. Gebruder Jungshans G.m.b.I-I., Schramberg, Germany Filed Nov. 12, 1969, Ser. No. 875,646 Claims priority, application Germany, Nov. 21, 1968, G 68 07 990 Int. Cl. G04b 15/00 US. Cl. 58-116 3 Claims ABSTRACT OF THE DISCLOSURE Continuous-switching device advancing the wheel mechanism of an electric clock, which device comprises a movement-controlling oscillator preferably driven by electromagnetic means, a two-armed switching armature driven by this movement-controlling oscillator, and a ratchet wheel driven by the said switching armature, characterized in that the switching armature (11) is unequally armed and the ratio between the arm lengths is about 2:3, furthermore in that the armature aperture angle equals or exceeds 90; and that the distance (a) between the switching armature pin (12) and the ratchet wheel pin (20) equals or exceeds a value of 0.8 times the diameter (D) of the ratchet wheel (18).

The invention relates to a continuous-switching device for advancing the wheel mechanism of an electric clock, which device includes a movement-controlling oscillator preferably driven by electromagnetic means and a twoarmed switching armature driven by this movement-controlling oscillator, and a ratchet wheel driven by the said switching armature.

In clocks with a driving movement-controlling oscillator, driven e.g. electromagneticallv and without contacts via an electronic circuit, in which clocks the drive of the wheel mechanism is derived mechanically from the movement-controlling oscillator, the structure of the continuous-switching device is of special importance since an additional load to the oscillator is to be avoided as much as possible.

The invention aims at providing a continuous-switching device which operates with a particularly high efficiency. This is achieved, according to the invention, by means of an unequally-armed switching armature in which the ratio between the arm lengths is about 2:3, furthermore by means of an armature aperture angle of 90 or more, and finally by means of a spacing between switching armature shaft and rachet-wheel shaft which equals or exceeds a value of 0.8 times the diameter of the wheel.

The invention is explained below in greater detail by means of an embodiment with the aid of the drawing. In the drawing, there are shown in FIG. 1, a plan view of an embodiment of the continuous-switching device of the invention;

FIG. 2, a further plan view of the continuous-switching device as in FIG. 1, but with another position of the switching armature; and,

FIG. 3, a side view of the continuous switching device of FIG. 2.

In the figures, numeral indicates a part of a sheet bar of a wheel mechanism. Numeral 11 represents a switching armature of the wheel mechanism. Its pivot pin 12, besides being supported in other places, rests pivotably in sheet bar 10. Arm 110 of switching armature 11 is shaped as fork which is engaged e.g. by an elliptical switching element of a movement-controlling oscillator, preferably of a balance wheel whereby the swing of fork 11 is 3,611,707 Patented Oct. 12, 1971 effected. The movement-controlling oscillator of the wheel mechanism is of the usual kind. It is not shown in the drawing. It can be driven in a known manner Without contacts by electromagnetic means via an electronic switch.

The switching movement of the switching fork 11 is limited by two stop pins 13 and 14 which may be constructed as magnetic pins so as to hold the armature fork in its terminal positions. In the embodiment shown how ever, non-magnetic pins 13 and 14 are provided while a permanent magnet 15 is provided for holding the switching fork in its terminal positions, this magnet cooperating with switching fork 11 which consists of ferromagnetic material. To obtain a holding force in the terminal positions, an opening 11d is provided in switching fork 11.

Switching fork 11 has two arms 11a and 11b provided at their ends with pallets 16 and 17. These pallets may be stones or consist of steel. It is of course also possible to use, instead of the pallets shown in the drawing, pin pallets which are inserted in the switch arms so as to be perpendicular to the plane of the switching armature. Instead of the pin pallets, round pins of stone or steel may of course also be provided.

According to the invention, arms 11a and 11b of switching armature 11 are of unequal length, the ratio between the shorter armature arm 11a and the longer armature arm 11b being approximately 2:3. The armature aperture angle a exceeds Pallets 16 and 17 cooperate in the known manner with the teeth 18a of the ratchet wheel 18 which is mounted on shaft 20. The distance a between pivot pin 12 of switching fork 11 and pin '20 of ratchet wheel 19, according to the invention, equals or exceeds a value of 0.8 times the diameter D of ratchet wheel 18. Another ratchet wheel 19 is fastened to pin 20 of ratchet wheel 18 which ratchet wheel 19 cooperates with a retaining spring 21. Retaining spring 21 is preferably provided at its free end with a stone 22 which engages the teeth of ratchet wheel 19. The retaining spring is provided with a bent flange 21a in which an opening 21b is provided. This opening is engaged by an eccentric 24, rotatably mounted in a sheet bar of the wheel mechanism. In this manner the position of stone 22 with respect to ratchet wheel 19 is adjustable. Furthermore, another eccentric 23 is provided which is likewise rotatably fastened in a sheet bar of the wheel mechanism. The initial stress in retaining spring 21 can be adjusted by means of this eccentric 23.

A known-type pawl shaped as double pawl, which engages the ratchet wheel teeth directly, may also be used in place of retaining spring 21 shown.

Tests have shown that the efficiency of the continuousswitching device of the invention is considerably greater than that of known continuous-switching devices.

What is claimed is:

1. In a continuous-switching device advancing the wheel mechanism of an electric clock, which device comprises a movement-controlling oscillator preferably driven by electromagnetic means, a two-armed switching armature having terminal positions and driven by said movement-controlling oscillator, and a first ratchet wheel driven by said switching armature, said armature and said wheel individually pivoting about pin means, the improvement comprising:

said switching armature being unequally armed and having a ratio between the arm lengths of about 2:3; said first ratchet wheel having an armature aperture angle a equaling or exceeding 90;

said device having the distance (a) between the switching armature pivot pin and the first ratchet wheel pivot pin equal to or exceeding a value of 0.8 times the diameter (D) of the ratchet wheel;

a second ratchet wheel having a retaining spring and being associated with said first ratchet wheel, said 3 4 spring having a second ratchet wheel engaging position of the spring with relation to said second ratchet terminus th re n; d wheel and the prestress of said retaining spring.

said switching armature being of ferromagnetic material and having an opening therein, a permanent magnet References cued being laterally associated with said switching arma- 5 UNITED STATES PATENTS ture, said magnet producing forces of attraction hold- 3,059,500 10/1962 Schneiter 5828 ing the switching armature at said terminal positions. 3,462,942 3/1969 Meitingef et a1 5 3,488,942 1/1970 Hougendobler 5 8 28 2. The continuous-switching apparatus as in claim 1, whereln thearms of the swltchrng armature are provided 10 RICHARD B. WILKINSON, Primary Examiner with pallets of steel or stone.

3. The continuous-switching apparatus of claim 1, in- SIMMONS Asslstant Exammer eluding two rotatable eccentrics associated with said re- U CL X R taining spring, said eccentrics independently adjusting the 15 74-l.5 

